As digital media technology continues to advance, and the cost of storage continues to decline, users increasingly host and consume digital media content on their own primary computers (e.g., desktop PCs). Examples of such digital media include music, video, still images, and so on. So, this means that increasingly users are listening to digital music, watching digital video, and viewing still images (e.g., photographs) on their home or business computers.
At the same time, the corresponding increase in the availability of portable media-playback devices such as personal digital assistants (PDAs), digital media players (e.g., so-called “MP3 players”), hand-held computers, laptop computers, and smart phones is providing users more ubiquitous access to digital media content than ever. As users rely more and more on such portable computing devices, there is a growing need for applications that effectively transfer digital media from source devices, such as primary computers, to the portable devices.
However, the existence of the multitude of media content formats complicates the transference of digital media content from source devices to target media-playback devices. This multitude of media content formats raises issues about format compatibility with target media-playback devices and management of legal rights for transferred media content.
Digital media content typically exists in a specified “format.” Herein, a “format” of digital media content includes its specific pre-established arrangement or organization of media data in computer-readable storage media. In addition, media data is typically compressed (and later decompressed) using a specific compression/decompression (“codec”) algorithm. Because a media format and its specified codec are often closely associated, the line between them is often blurred. Herein, unless the context indicates otherwise, references to the “format” of digital media content includes the codec associated with compressing/decompressing the content, as well as the content's specific pre-established arrangement or organization of media data in computer-readable storage media.
There is a variety of conventional and available formats of digital media content. Some formats are generally available with low or no commercial encumbrances (e.g., paying of royalty fees). Examples of these widely available formats include WAV, MPEG audio layer 3 (commonly called “MP3”), and AVI. Others formats are proprietary; therefore, the uses of these formats often are controlled by licensing agreements. Examples of these proprietary formats include the Adaptive Transform Acoustic Coding (Atrac®) format from the Sony Corporation; the RealAudio™ format from RealNetworks, Inc., the QuickTime™ format from Apple Computers, Inc. and Windows Media Audio (WMA) and the Windows Media Video (WMV) formats from the Microsoft Corporation.
Typically, a media-playback device is designed to handle one or more specific formats of the digital media content (“formatted-media-content”). Due to space, processing-power, memory, and licensing constraints, these playback devices typically have a limited set of compatible formats. Often, a device manufacturer licenses the technology for playing formatted-media-content in a proprietary format, such as those formats listed above. Sometimes, the device manufacturer implements its own proprietary format technology.
Since a target playback device typically employs a different or slightly altered format than does the source device (e.g., desktop PC), the format of formatted-media-content is typically altered before being transferred from the source device to the target device. This format-alteration is commonly called “transcoding.”
A transcoding process may include, for example, converting a formatted-media-content from one format to another (e.g., MP3 to WMA), so the newly formatted content will play on the playback device. Furthermore, a transcoding process may include, for example, down-sampling the formatted-media-content to a lower bit rate to reduce the amount of storage space needed on the playback device, or adapting the screen size of the formatted-media-content, so video appears correctly on the playback device.
When transcoding, the formatted-media-content is sometimes converted into a format having lower processing requirements for decoding. A formatted-media-content configured for playback on a full-scale “desktop” computer may be too complex to decode effectively on a device with a lower-powered processor, such as a portable media-playback device. Furthermore, when transcoding, the formatted-media-content is sometimes converted into a specific format (e.g., a proprietary format) employed by the target media-playback device.
There are many different conventional approaches employed when transferring formatted-media-content from a source device to a target media-playback device. Many of those conventional approaches include transcoding the formatted-media-content into a format compatible with, and/or preferred by, the target device (“compatible/preferred format”).